Multi-radiation large area detector

Abstract

A radiation detector having glass emitting photons by scintillation in response to incident neutrons and/or electromagnetic radiation of at least about 1 keV, and a system associated with the glass for detecting the presence of photons emitted by scintillation. The glass ceramic material is a fluoride glass matrix having nanocrystalline particles distributed therein substantially all of which are in a phase that scintillates with average diameters of less than about 100 nm in a fluorozirconate matrix. Various metals are disclosed for the ceramic particles and methods of manufacture are also disclosed.

1 . A radiation detector, comprising a glass emitting photons by scintillation in response to incident neutrons and/or electromagnetic radiation of at least about 1 keV, and a system associated with said glass for detecting the presence of photons emitted by scintillation.  
     
     
         2 . The radiation detector of  claim 1 , wherein said glass emits photons by scintillation in response to incident radiation of up to 100 MeV.  
     
     
         3 . The radiation detector of  claim 1 , wherein said glass emits photons by scintillation in response to incident radiation of up to 20 keV.  
     
     
         4 . The radiation detector of  claim 1 , wherein said glass emits photons by scintillation in response to incident neutrons of at least 0.0025 eV.  
     
     
         5 . The radiation detector of  claim 1 , wherein said glass is a plurality of layers in substantial registry, each layer emitting photons by scintillation in response to incident neutrons and/or electromagnetic radiation of different energy levels.  
     
     
         6 . The radiation detector of  claim 1 , wherein said glass has nanocrystalline particles therein substantially all of which are hexagonal phase.  
     
     
         7 . The radiation detector of  claim 1 , wherein said glass has nanocrystalline particles therein having average diameters of less than about 100 nanometers (nm).  
     
     
         8 . The radiation detector of  claim 1 , wherein said glass has nanocrystalline particles therein having average diameters of less than about 20 nm.  
     
     
         9 . The radiation detector of  claim 1 , wherein a neutron moderator is present between said glass and a source of neutrons.  
     
     
         10 . The radiation detector of  claim 9 , wherein said neutron moderator is polyethylene.  
     
     
         11 . The radiation detector of  claim 1 , wherein at least some of said glass is in the form of adjacent tiles with material having substantially the same index of refraction between said tiles.  
     
     
         12 . The radiation detector of  claim 1 , wherein said system includes a camera for detecting optical events resulting from incident neutrons and/or electromagnetic energy impinging said glass.  
     
     
         13 . The radiation detector of  claim 12 , and further including a reflector on one side of said glass.  
     
     
         14 . The radiation detector of  claim 13 , wherein said reflector is a dielectric.  
     
     
         15 . The radiation detector of  claim 1 , wherein said glass is a transparent ZBLAN heavy metal fluoride glass with not less than about 35 mole % Zr fluoride.  
     
     
         16 . The radiation detector of  claim 1 , wherein said glass includes an arcuate portion.  
     
     
         17 . A glass ceramic material which scintillates upon incident neutrons and/or electromagnetic energy of at least 1 keV comprising a fluoride glass matrix having nanocrystalline particles distributed therein.  
     
     
         18 . The glass ceramic material of  claim 17 , wherein said nanocrystalline particles have average diameters less than about 100 nm.  
     
     
         19 . The glass ceramic material of  claim 17 , wherein said nanocrystalline particles have average diameters less than about 20 nm.  
     
     
         20 . The glass ceramic material of  claim 17 , wherein said fluoride glass matrix contains at least 35 mole % Zr ions together with ions selected from the group consisting of alkali and alkaline earth ions, at least 5 mole % of the fluoride ions replaced by Br and/or Cl ions, and at least 0.1 mole % cations present are selected from the group consisting of transition metal ions, rare earth metal ions, Al, Sn, Bi, In ions, Ga ions, Tl ions, Pb ions and mixtures thereof.  
     
     
         21 . The glass ceramic material of  claim 17 , wherein said fluoride glass matrix contains lithium 6 ions.  
     
     
         22 . The glass ceramic of  claim 17 , wherein said glass is a transparent ZBLAN heavy metal fluoride glass with not less than about 35 mole % Zr fluoride.  
     
     
         23 . The glass ceramic of  claim 22 , wherein a light sensitive rare earth element is present therein.  
     
     
         24 . The glass ceramic of  claim 23 , wherein said light sensitive rare earth element is one or more of Eu, Sm Ce, La and mixtures thereof.  
     
     
         25 . The glass ceramic of  claim 24 , wherein said rare earth is Eu present at a concentration of not less than about 0.1 mole %.  
     
     
         26 . The glass ceramic of  claim 17 , wherein said glass ceramic is transparent.  
     
     
         27 . A method for making a glass-ceramic material containing nano-crystalline particles with average diameters of less than about 100 nm in a fluorozirconate matrix, comprising mixing ZrF 4 , an alkali fluoride, an alkaline earth fluoride, a fluoride of a tri-valent metal selected from the group consisting of transition metal ions, rare earth metal ions, In ions, Ga ions, Tl ions, Pb ions and mixtures thereof, together with a bromide compound selected from the group consisting of alkali and alkaline earth bromides, such that zirconium fluoride is present in a concentration of at least 35 mol % and bromide ions are present in a concentration of at least 5 mol % in the glass-ceramic, heat treating the fluorozirconate matrix at a temperature and for a time sufficient such that substantially all of the nano-crystalline particles are in a phase that scintillates, and thereafter cooling the mixture to room temperature.